Tappet wrench



March 20, 1962 R. G. BROWN 3,025,732

TAPPET WRENCH Filed March 29, 1960 I4 32 28 I8 Fig 3o 34 INVENTOR.

4 ROBERT 6. BROWN 7 #W ATTORNEYS ilnite tare 3,025,732 TAPPET WRENCH Robert G. Brown, Birmingham, Mich, assignor to Eaton Manufacturing Company, Cleveland, Ohio, a corpora tion of Ohio Filed Mar. 29, 1960, Ser. No. 18,393 2 Claims. (Cl. 8113) Broadly, this invention relates to tappet adjusting equipment but more specifically pertains to a tappet holding wrench utilized in valve gear arrangements found in internal combustion engine mechanisms.

In the environment of an internal combustion engine there is utilized, for example, mechanical and hydraulic tappet arrangements wherein the operation of the valve mechanism is accomplished through the gear train reaction initiated by a cam shaft rotation imparting a reciprocatory motion to a tappet which in turn imparts this motion to a push rod and valve stem. In the course of operation of the engine unit, it becomes necessary and essential to the eflicient functioning of the engine to provide for the adjustment of the tappets, automatically or or manually, and thereby compensate, for example, for the problem of insuflicient opening of the valves or the incomplete closing thereof on the valve seat. This novel tappet wrench is adaptable to a manually adjusted tappet and functions to maintain the tappets in a position fixed from rotation within the tappet bore thereby allowing a mechanic or operator to make the necessary adjustment. Tappets to which the wrench is specifically applied are of the type having an adjusting screw at one end portion thereof with this adjusting screw serving to selectively provide or take up the lash necessary to completely close the valve during the operating cycle. Therefore, this wrench has specific applicability in tappet arrangements whereby an adjustable screw or similar adjusting means is located on the tappet body and it becomes essential that the tappet body be fixed from rotation within the bore so that the compensating adjustment can be properly made on the screw.

In the past, tappet wrenches utilized in the same specific environment were designed so that a tongue or extended flange portion on one end of the Wrench was inserted into a hole in the body of the tappet and the end of the wrench remote from the extended flange was engaged with the adjacent tappet in such a manner as to prevent the tappet in which the tongue was inserted from rotating within the tappet bore. These wrenches proved unsatisfactory in that the structure was limited to a single tongue on the wrench and to complete the adjustment of an entire tappet arrangement, it necessitated the use of two dissimilarly configurated wrenches to accommodate all the positions of the tappets.

Therefore, it is an object of this invention to devise a novel tappet wrench which functions to maintain the tappet to be adjusted, rotatably fixed within the tappet bore and by such positioning, enable the operator thereof to readily adjust the tappet to the desired overall tappet length.

Another object of this invention is to devise a tappet wrench capable of servicing all positions of tappet location in an internal combustion engine whereby the wrench may be reversed and thereby service all of the above mentioned positions.

It is another object of this invention to provide a tappet wrench whereby the wrench is formed from strip stock material or the like having the end portions thereof operable to engage openings in a tappet body and having the center portion thereof operable to engage the adjacent tappet bore when either end is used.

It is still another object of this invention to provide a tappet wrench which is simple and economical in its production and is operable to service a combustion engine utilizing a tappet adjusting feature and wherein the tappet body must be fixed from rotation prior to the adjustment thereof.

Further objects and advantages of the invention will become apparent from the following description taken in connection with the drawings forming a part of the specification and in which:

FIGURE 1 is a top view of the tappet wrench;

FIGURE 2 is a side elevational View of the tappet wrench shown in FIGURE 1.

FIGURE 3 is a top view of the adjusting wrench as applied to the tappet body and located in the adjacent tappet bore.

FIGURE 4 is a side sectional view of the tappet wrench and tappet structures in their respective bores taken along lines 44 shown in FIGURE 3 and further illustrates the positioning of the end portions and middle portion of the wrench as it applies to the tappet bodies located within the tappet bores.

Referring to FIGURES 1 and 2 of the drawing, the tappet adjusting wrench 10 comprises a main body portion 12 and a pair of end portions 14 and 16 formed thereon. The wrench is formed in a substantially channel shaped configuration having a pair of upwardly extending flange portions 18 and 20 integral with the main body portion 12 and extending in a parallel direction to one another throughout the axial length of the body portion. The functional reasons for providing the Wrench with flange portions 18 and 20 are for increasing the overall structural strength of the wrench also providing a gripping area for the operator to place the tool in and remove it from its operable position. Flange 20 has an interrupted section therein defining an opening in which a flange 22 is formed and extends in a direction opposite to that of flange 20 having a width substantially equal to that of flange 20. Flange 22 is formed substantially at the longitudinal central portion of the wrench and has a pair of end surfaces 24 and 26 thereon. Flange 22 serves a. purpose which will be described later in detail. Flange 18 of the wrench is axially bounded by a pair of cut out portions or spaces 28 and 30 whereby these spaces facilitate the bending or forming of the wrench material in a manner so as to provide the lateral spacing of the end portions 14 and 16 in relationship with the axis of the body portion 12. Adjacent the spaces 28 and 30 on the end portions 14 and 16 are a pair of tongues or projections 32 and 34 which extend in the same direction as the direction of flange 22. Therefore, it can be seen from this description that the general formation of the wrench requires a relatively simple forming operation in which the conforming of the material to the desired configuration can readily and easily be obtained.

FIGURE 2 of the drawing more clearly illustrates the end portions 14 and 16 of the wrench and'particularly illustrates the projections 32 and 34 on the end portions and the direction thereof with respect to flange 22.

FIGURES 3 and 4 of the drawing illustrate the wrench in its operable position with respect to the tappet bodies in the tappet bores. The tappets 36 and 38 disclosed in the drawing are of the adjustable mechanical type having a body portion 40 and an adjusting screw 42 threadedly engaging the body portion. The tappet bodies are disposed in suitable bores 44 and 46 formed in the engine block 48 with each tappet having a base portion 50 engageable with a rotatable cam 52 fixed to a rotatable shaft 54. By rotation of the shaft, the cam imparts a reciprocatory motion to the tappet body and thereby allows the tappet body to slide within the tappet bore. The adjusting screw 42 located on the upper portion of the body is centrally disposed within a series of openings 56 formed in the end portion of the tappet body with these end portions being of a depth substantially equal to the length of the projections 32 and 34 extend ing from the end portions of the wrench and which are insertable in these openings. This depth is not critical but must be suflicient to hold the projections so that they cannot readily slip out.

The wrench is positioned by the operator in a manner whereby the projection 32 of the end portion 14 is inserted into one of the openings 56 in the tappet body 46 of tappet 36, preferably as shown in FIGURE 3, placing the tappet in a position within the bore 44 so that the bent configuration of the end portion 14 of the wrench is utilized in bypassing the adjusting screw 42 of the tappet and thereby orientates the flange 22 with the adjacent tappet bore 46. The flange 22 is of a length adaptable to have the axial end surfaces 24 and 26 thereof engageable with the periphery of the adjacent bore 46 such that when the adjusting screw is rotated, longitudinal movement of the wrench is prevented by the engagement of the end surface 26 with the tappet bore 46. Of course, which end (24 or 26) of the flange 22 reacts against the adjacent tappet bore 46 depends upon the direction of rotation imparted to the adjusting screw. Therefore, by rotating the adjusting screw, a component of force is imparted along the axial length of the wrench and because of the engagement of flange 22 with the periphery of the tappet bore, movement of the wrench is prevented which prevents rotation of the body 40 of tappet 3d within the tappet bore 44. When the wrench has been so positioned it can be readily seen that the rotation of the adjusting screw can be performed, turning same to its desired position and thereby increase or decrease the amount of lash that is existing in the valve gear train arrangement. The amount of such adjustment is accordingly determined by the operator.

FIGURE 4 clearly illustrates the manner in which the wrench is positioned and the necessity forits particular configuration in its arrangement with the tappet bodies located in the tappet bores and with the relative location of one tappet to another.

The unique utility of this tappet wrench lies in the fact that each end portion thereof is adaptable to function in the same manner with respect to one another and the flange 22 is readily adaptable to function with either end of the wrench. Therefore, in an arrangement where the tappet to be adjusted is the last tappet in the line and there is not a succeeding tappet bore, the end portion 16 of the wrench can then be utilized. For example, in FIGURE 3, assume that tappet 36, in which the projection of the wrench is engaged, as shown, is the second to the last tappet 38 in the row of tappets located in the block 48 of the internal combustion engine. With prior known tappet holding tools, it was generally impossible to adjust the last tappet with the same tool since it was necessary for the holding wrench to associate itself with the succeeding adjacent tappet bore in the row. In this same situation, applicants tool can be reversed, that is, the end portion 16 can be employed and projection 34 inserted into one of the openings 56 formed in the tappet body of tappet 38 and the flange 22 can thus be placed in the tappet bore 44 of tappet 36. By repositioning the Wrench, the adjusting screw on the last tappet in the row can be rotated and the body portion will be restrained from any rotative movement within the tappet bore by the engagement of the end surfaces 24 or 26 of flange 22 with the periphery of the bore 44. Thus by the interchangeability of the ends of the tool, the novel feature of having one tool for rotatably fixing any tappet located in a normal engine block arrangement has been provided.

While the present invention has been described in con nection with certain specific embodiments, it is to be understood that the foregoing description is merely exemplary and that the concept of this invention is susceptible of numerous other modifications, variations, and applications which will be apparent to persons skilled in the art. The invention is to be limited therefore, only by the appended claims.

What I claim is:

1. A tappet holding tool comprising a body portion, a pair of end portions on said body portion, said end portions being substantially symmetrically disposed on said body portion with each end having a projecting portion depending therefrom, said body portion having a projection depending therefrom and centrally located intermediate the end portions, said projections all extending in the same direction with respect to the body portion, and said body projection and being selectively cooperable with either of said end projections whereby when the tool is positioned to cooperate with a tappet bore, rotation of a selected tappet is prevented.

2. A wrench for restraining rotative move-ment of a tappet within a tappet bore comprising, a body portion, a first end porton and a second end portion disposed on the body portion, projecting means on said first and second end portions selectively engageable with a tappet body and extending in a direction substantially perpendicular to the axis of said wrench body portion, projecting means on said wrench body portion extending in the same direction with said means on said end portions and centrally located therebetween and adaptable to engage a tappet bore adjacent said first mentioned tappet bore, said means on said end portions being selectively cooperable with said projecting means on said body portion to restrain rotative movement of said tappet.

References Cited in the file of this patent UNITED STATES PATENTS 2,468,983 Johnson May 3, 1949 

